It is well known in the art that imparting orbital motion to a blade in a reciprocating saw greatly improves the cutting accuracy. The blade is moved in an orbital path so as to cause the saw teeth to cut into the workpiece during the pull stroke and to lift free of the workpiece during the return stroke.
As a result of the blade lifting free of the workpiece during the return stroke, the teeth do not rub against the workpiece. This leads to improved efficiency and reduced vibration; and sawdust and waste chips can be more effectively removed from the cut.
Many complex orbital-action saws have been developed, but typically these systems are awkward and expensive to manufacture due to their complexity. In addition, the complex internal motions generated by these systems make them not easily adaptable to heavy-duty, rough-cutting or industrial reciprocating saws. Similarly, this added complexity prevents orbital-action mechanisms from being used on inexpensive saws.
Such complex reciprocating saws are disclosed in U.S. Pat. No. 5,212,887 to Farmerie, U.S. Pat. No. 4,628,605 to Clowers, and U.S. Pat. No. 2,705,980 to Papworth.
A major limitation of these saws is that the orbital path of the saws provides cutting in only a limited portion of the rotational travel of the driver mechanism, thus resulting in poor cutting efficiency.
Another limitation of prior art saws is that they have complex mechanisms which are difficult to manufacture.
Accordingly, it is desirable to develop a reciprocating saw with orbital action which is adaptable for use in both heavy-duty industrial and inexpensive consumer environments to achieve improved cutting efficiency.